Functional evaluation of pituitary reserve in patients with the amenorrhea-galactorrhea syndrome utilizing luteinizing hormone-releasing hormone (LH-RH), L-Dopa and chlorpromazine

Functional pituitary reserve in 18 patients with the amenorrhea galactorrhea syndrome was evaluated using luteinizing hormone releasing hormone (LH RH), L dopa and chlorpromazine. Gonadotropin release after administration of synthetic LH RH varied widely from that seen in normal women to that below the normal range; however, cases with pituitary tumor exhibited the lowest responses or no responses to LH RH. Prolactin release in response to drugs which normally either stimulate (chlorpromazine) or inhibit (L dopa) its secretion, also varied widely regardless of the presence or not of a pituitary tumor. It is concluded that LH RH is a reliable test to determine the pituitary reserve in cases of galactorrhea associated with amenorrhea. These results suggest that high prolactin levels associated with a deficient secretion of gonadotropin in response to LH RH may be indicative of an underlying pituitary tumor, even in the absence of sellar enlargement.